Nigel the 1977 MGB - Top End Assembly

[@jimvierra7970]

This is a great video and will help me immensely. I've been wanting to refresh the head to my 78B and wasn't sure on exactly how to take on this project but this makes me confident that I can undertake this much needed task with this instruction. Keep up the good work.

[@brianaslett4154]

Well put together video. I liked the leak down test - didn't do that on mine. I noticed that you did not put shims under the middle two rocker pedestals. Apparently they're needed to stop any movement of the rocker shaft. Moss USA part number 460-255. They were not fitted to my head so I fitted them when I changed the blown head gasket. I didn't fit the valve guide seals on top of the valve guides, just used the neoprene "o" rings under the cotters which seem to work well enough - mine uses almost no oil.

[@donthuis]

I had the same remarks: on more than one KZbin video on mounting cylinder heads these special 0,005" shims are missing, although its addition is already from way back. I had the later VITON valve stem seals in store but also kept the simple O rings under the cotters that seemed to work well with an oil usage of less than 1 litre for 2500kms/1500miles for this block

[@markstern8699]

Great video and very informative!

[@maneki9neko]

I love the detail in these videos. This said, in Abingdon, those studs were installed without thread cement. Removing 'red' Loctite typically requires heat from a torch to break loose the part without risk of distorting the shaft. When half of the thread is in a massive block like this, it can require a LOT of heat on the stud shaft. This is so much the case that degrading the heat treat on the stud is a concern. In these kinds of applications the weaker grades of Loctite are your friends. Purple Loctite is easy to break loose with a wrench, but will never move from vibration. The next step up is 'blue' which can take some effort to remove, but almost never requires a torch. Red Loctite was designed for situations in which the parts will almost certainly never be separated. On a restored car, many see value in leaving the next restorer an unobstructed path to rebuilding.

[@AlexPlatacis]

Great input. I very seldom use thread lockers. In this case I used what I had. Your explanation of the grades is very helpful. Hopefully others will benefit. Thanks

[@donthuis]

I got the same advice from my MG Mech never to use Red Loctite for this very reason (I have the blue variety in store only). On my I.S. block on which I just resolved a hanging valve issue, the 11 large studs were mounted with IMHO Red thread sealer and half of them could NOT be removed at all without heating them, so I left them all in situ and cleaned around them. Removal of these studs makes cleaning and checking flatness of the block surface much easier and it also keeps the option for changing from regular studs to ARP ones open in an easy way. I found the existing OEM studs fine, but an ARP modification requiring a flame would've been a tricky job

[@stevegnome]

Thats a great spring compressor - haven't seen one like that before!

[@AlexPlatacis]

only $12 at Harbor Freight. www.harborfreight.com/universal-overhead-valve-spring-compressor-59343.html

[@donthuis]

I have the same, from the time I had a Gold Seal block with single valve springs on which this works. With the double springs on an earlier head on my present block it does NOT. I had to put the head under my column drill machine and use some extra part to press the lot down. There are also other types of spring compressors for jobs when the head remains in situ with the rope trick between head and piston and which use the rocker shaft as leverage point for such a tool.

[@donthuis]

Normally torqueing the 11 larger headstuds is made in two steps not one: first one e.g. on 25 lbf, second one on 50 lbf (or 55lbf/74,5Nm, the later max value indicated by British Leyland in a TSB) Text: "The cylinder head torque on the MGB can be increased from the present 45-50 Ibs./ft. to 50-55 Ibs./ft. This information should be inserted in the appropriate section of your Workshop Manual".

[@AlexPlatacis]

Great tip I seem to remember doing that... Could be I breezed over that detail or cut it out because the video was getting too long. Also I re-torqued after break-in run Thanks for the comment.

[@donthuis]

@@AlexPlatacis OK, then I only think about the length of this break-in run. I warmed the block up fully at first at home and then made one 10km drive on the highway for a single heatcycle and then retorqued and reset valve clearances after cooldown. This was because I remembered the single heatcycle being prescribed for Payen headgaskets and my I.S.block also came with a notice any retorqueing by me as a buyer was forbidden! It seems composite headgaskets are designed to deform when heated once only.. Well recorded video though, many on KZbin have shaking images or blocked details: welldone!

[@AlexPlatacis]

Btw. That is a good tip about composite head gaskets. Not too many people know the differences between then and the copper ones. As parts become harder to find, decision making will be based on availability. The physical differences and how to use them will be important distinctions

[@anthonygowland8363]

Thanks for sharing

[@steves-lockerfinds]

Hey Alex long time. Dad told me of your channel cool car how is Mike much love.

[@AlexPlatacis]

Ha ha... Your like Mark Wahlberg "Say hello to your mutha"

[@windmill1965]

Thank you for this extensive video, showing the entire process from beginning to end. One thing I would do different is the torqueing of the studs. Instead of immediately torqueing to the final value I would do one step in between. For example: torque all bolts first to 40 ft.lbs before doing the final round with 50 ft.lbs. Edit: do you have a similar video about the lower part of the engine?

[@AlexPlatacis]

Thanks... I had considered two stepping the torque, but after research I found that it was not standard practice for this engine. torque specs being pretty specific for some newer vehicles I decided not to let my experience with those bias the process.(Kept it simple) yes, I do have a few other videos on the lower end. I will make a new play list with just engine videos for this car. (good idea)

[@AlexPlatacis]

here is the play list Enjoy... kzbin.info/aero/PL2RsH7Pa3wcFG_bFfgxVmPvrD-6B8os07

[@windmill1965]

@@AlexPlatacis Thank you for creating this playlist. I binge watched all videos, oldest first. I have a 1964 MGB. The history of this car is unknown. Sooner or later in the future I will have to look inside the engine and gearbox to check the status of the components. Your videos help to allay the trepidation of starting such a job. And pinpoint what to pay attention to.

[@maneki9neko]

I agree with you. Torquing to 80% and then taking the torque to the final value brings the head down straighter, and there is less lateral motion in the gasket as it is tightened. This is a good practice. That said these are quite basic engines, and the head is cast iron.

[@chrisedwards3482]

Alex Platacis Alex, thank you for this very informative video. I do have a couple of questions if I may. You suggest torquing up the 4 rocker shaft pedestal nuts after torquing up the 11 head nuts to 50 lb.f. What should the torque be on these 4 nuts? Also 50? My job was just replacing leaking valve stem oil seals so I only took the head off ( and manifolds, carbs, radiator hoses etc). I didn’t disturb the block so the distributor stayed in place. I don’t have facilities or ability ( maybe it’s confidence really) to strip the head so I got a professional to strip a spare head I had and give it back with new valves and seals in place. Once I took the old head off, I discarded the “old” head but kept the rocker shaft assembly from it, and kept the “old” pushrods. This was mainly because the “new” head rocker assembly had a different cup and ball on the rockers and I thought it best to keep rockers and pushrods as a set. So I am now replacing the “old” rocker shaft assembly on to the “new” head, and I have not changed the settings on the tappets. So I am just putting it back as it was, except there was only one shim when I took it out, I am putting it back with two shims, one under each of the two middle pedestals. ( it is an older 1970 engine so should have 2). Before reassembling I brought No 1 and No 4 pistons to the top of their travel, but I don’t know if 1 or 4 is on the compression stroke. Your video shows you feeling inside the block, but I don’t have those access covers off and don’t really want to disturb them. Does it really matter as the tappet settings that were working have not been disturbed? If it does matter, can I tell by the position of the pushrods?

[@AlexPlatacis]

so lot to cover... First thing I'd mention is to be sure the oil hole matches on the new head and your old rocker assembly. There were a few types Here is a video on that kzbin.info/www/bejne/j2fPd5h7mZaSiposi=pq_gi4SOudfad4bt

[@AlexPlatacis]

yes you can tell if cylinder 1 is at TDC in compression stroke by using the push rods. They should both be short

[@AlexPlatacis]

this link shows most of the relevant Torque settings for an MGB. in here is suggests 25 ft pounds for the rocker bracket nuts. (which seems about right) acrobat.adobe.com/link/track?uri=urn%3Aaaid%3Ascds%3AUS%3Add9348b1-7d86-4ad8-af47-a15030c943bc&viewer%21megaVerb=group-discover